Soft calibration in a flow system with electrochemical detection Application to the determination of phenolic compounds

method is proposed for the simultaneous determination of phenolic compounds in continuous flow with electrochemical detection. This detector has high sensitivity and was used in the scan mode such that complete voltammograms were obtained which were then analysed using multivariate regression techniques (partial least squares, PLS). Likewise, given the multivariate character of the recorded signal, in the prior optimisation stage, a parameter, the net analyte signal (NAS), was used, which allow one to optimise the first-order instrumental response. The multivariate technique used allow us to determine 4-nitrophenol, phenol and p-cresol simultaneously. The mean of the absolute values of the relative errors obtained for 4nitrophenol, phenol and p-cresol is 0.8, 4.3 and 7.8%, respectively.